Many attempts have been conventionally made to increase the molecular weights of various compounds which are to be contained in silver halide photographic materials or in developing solutions for use in the development of the photographic materials.
For example, attempts have been made to increase the molecular weights of stabilizers such as mercapto group-substituted heterocyclic compounds which prevent fogging from being caused by the formation of a nucleus which induces development even when silver halide photographic materials are not subjected to exposure to thereby prevent the compounds from being diffused in adjacent light-sensitive layers and from being dissolved out into processing solutions and to thereby prevent a reduction in spectral sensitivity from being caused by the desorption of sensitizing dyes.
There are disclosed high-molecular compounds having repeating units, as residues of stabilizer, derived from thiazoles (U.S. Pat. No. 3,598,599), tetrazoles (U.S. Pat. Nos. 3,576,638 and 4,134,768), imidazoles (U.S. Pat. No. 3,598,600), tetraazaindenes (JP-A-57-211142 (the term "JP-A" as used herein means an "unexamined published Japanese patent application")), benztriazoles (JP-A-59-90844), oxadiazoles, thiadiazoles, selenadiazoles and triazoles (JP-A-62-949), mercaptotetraazaindenes (JP-A-64-19343), oxazoles (JP-A-64-26843), thiosulfonic acids (JP-A-64-79742) and indazoles (JP-A-1-137247).
Further, attempts have been made to increase the molecular weights of couplers and ultraviolet light absorbers to thereby make them nondiffusing or to reduce the amount of high-boiling organic solvents for emulsification to thereby make layers thinner. Such attempts are described in U.S. Pat. Nos. 4,080,211, 1,247,668, 3,451,820, 3,926,436, 3,767,412, 4,431,726, 4,455,368, 4,464,463 and 4,443,534.
For the purpose of recovering and removing components in processing solutions by using anion exchangers, methods are disclosed in JP-B-58-22528 (the term "JP-B" as used herein means an "examined Japanese patent publication"), JP-B-60-28767, JP-A-62-75525 and U.S. Pat. Nos. 4,348,475, 3,437,631 and 3,253,920.
However, these methods for increasing the molecular weights of the compounds have disadvantages. For example, the polymerizability of starting monomers is poor and hence compounds having a sufficiently high molecular weight cannot be obtained so that the resulting compounds are poorly nondiffusing, or the compatibility of the compounds with hydrophilic colloids (e.g., gelatin) in silver halide photographic materials are poor. When the ion exchangers are used, the efficiency of ion exchange is low in conventional methods. Accordingly, it is highly demanded to develop a novel parent material for forming high-molecular compounds.